Author |
Topic: Rev counter not working. (Read 5083 times) |
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
 |
Rev counter not working.
« on: Jun 23rd, 2012, 8:01pm » |
 Quote  Modify
|
Hi all, the rev counter on my 2.0l 16v scorpio has stopped working, although when I disconnect the battery and then reconnect it the needle swings round as it should, so where does it take its signal pulse from and are there any diagrams here that I can use to trace the fault? Also not sure which fuse takes care of that circuit. Also having a problem with the battery discharging completely overnight sometimes, battery has been tested and is good, also fuseboxes have been stripped and rebuilt so no issues with moisture in them. Thanks.
|
|
 IP Logged |
My other car's a bike!
|
|
|
leewar
Senior Member
I'm a YaBB newbie!
Posts: 1504
|
|
Re: Rev counter not working.
« Reply #1 on: Jun 24th, 2012, 12:11am » |
Quote Modify
|
Is the light permanently on in the glovebox. Been a common cause
|
|
IP Logged |
|
|
|
Jonnycab
Senior Member
Former owner of 2.3 Ultima Facelift saloon
Posts: 3900
|
|
Re: Rev counter not working.
« Reply #2 on: Jun 24th, 2012, 2:32am » |
Quote Modify
|
Rev counter (as far as I remember) takes it's reading from the alternator....this could also be the reason the battery is losing charge overnight.....well not necessarily overnight, but insufficient charge from the alternator to the battery when the car is used would cause the battery to lose it quite quickly over the space of a few hours when the car isn't being used 
Have you checked the battery terminal voltage with a multimeter when the engine is running ?....should be between 13.8-14.2 volts. Anything less, then the alternator is probably faulty 
|
|
IP Logged |
|
|
|
Simmo
Administrator
I'm an OAP !
Posts: 5508
|
|
Re: Rev counter not working.
« Reply #3 on: Jun 24th, 2012, 7:42am » |
Quote Modify
|
If you look at Fault finder and scroll down to 'electrical' you may get the answer. Select 'voltage' which will take you to the detail of how to check the voltage from the instrument panel.
You may also find This useful.
The wiring diagram Here clearly shows that the alternator IS the source for the rev counter as Jon says.
|
|
IP Logged |
Now I'm an OAP
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #4 on: Jun 24th, 2012, 10:58am » |
Quote Modify
|
Hi again all, I have had the charging system checked out by my local motor factor guy who did the full range of checks on the battery and charging system, it is all working correctly and the battery itself is in tip top condition, I'm beginning to think that when I refitted the rebuilt main fusebox to the car that I might have disturbed the loom going to the instrument panel when I was reconnecting all the leads under the dashboard. I guess that is my next job to check out but any other suggestions will still be appreciated.
|
|
IP Logged |
My other car's a bike!
|
|
|
gozz
Senior Member
Been around awhile
Posts: 3475
|
|
Re: Rev counter not working.
« Reply #5 on: Jun 24th, 2012, 12:23pm » |
Quote Modify
|
My V6 cars received the tacho signal from the alternator,but I was under the impression that the 16v engines received it via the ignition,possibly the EDIS.
|
|
IP Logged |
|
|
|
Tompion
Administrator
1997 2.3 Ultima estate.
Posts: 2918
|
|
Re: Rev counter not working.
« Reply #6 on: Jun 24th, 2012, 12:27pm » |
Quote Modify
|
Beat me to it
In fact I think it was you who proved it by running the engine without a belt.
Only from the alternator on the 12v & diesel.
See here in the table for 3 pulses at the bottom of the page:
http://www.fordscorpio.co.uk/instreset.htm
“Shows the input frequency of the engine speed sensor, updated every second. This check allows the engine speed signal coming from the alternator, (12V V6, 2.5 TDi) or the EDIS (all others)”.
|
|
IP Logged |
ABS multiplug wheel sensor pins MK IV or MK 20
|
|
|
Tompion
Administrator
1997 2.3 Ultima estate.
Posts: 2918
|
|
Re: Rev counter not working.
« Reply #7 on: Jun 24th, 2012, 12:49pm » |
Quote Modify
|
on Jun 24th, 2012, 7:42am, Simmo wrote:
Glad you posted that Mike as I was looking for Snoopy's other diagrams, there are ones here that don’t appear to be on the link in the how to do things section.
I have a copy of the breakdown of the diagrams on my computer but didn’t know the link to post for others.
Anyone wanting to understand the diagrams better see the symbols PDF here:
http://www.drich2422.ukfsn.org/SCORPIO_WIRING%20DIAGRAMS/
|
|
IP Logged |
ABS multiplug wheel sensor pins MK IV or MK 20
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #8 on: Jun 24th, 2012, 6:23pm » |
Quote Modify
|
Well folks, I still have no rev counter, but along the way I now have no more flickering airbag light problems after soldering up the faulty pins on the instrument cluster, and also a problem I had with the o/s dipped beam not working is solved too, it was a dodgy dim dip relay that was causing that so at least some good news. Another thing I have noticed today when working under the bonnet is that one of the cooling fans seems to have a mind of its own even with the heater blowers switched off and the engine temp low, Should it do this or not? I do know that the fans are controlled by the large green relay behind the o/s headlight as disconnecting it stops the fans.
|
|
IP Logged |
My other car's a bike!
|
|
|
Simmo
Administrator
I'm an OAP !
Posts: 5508
|
|
Re: Rev counter not working.
« Reply #9 on: Jun 24th, 2012, 6:44pm » |
Quote Modify
|
on Jun 24th, 2012, 6:23pm, Bikerdon wrote:| Another thing I have noticed today when working under the bonnet is that one of the cooling fans seems to have a mind of its own even with the heater blowers switched off and the engine temp low, Should it do this or not? I do know that the fans are controlled by the large green relay behind the o/s headlight as disconnecting it stops the fans. |
|
According to This both should work together.
|
|
IP Logged |
Now I'm an OAP
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #10 on: Jun 24th, 2012, 7:04pm » |
Quote Modify
|
Thanks Simmo, will check the fans out, I was just unsure if any should be running with the A/C switched off and the engine cold, seems they should not so obviously another issue to look at. Ho-hum!
Ok, have checked the fans out and they are both running ok now, I still think they are running when they shouldn't be though.
|
|
IP Logged |
My other car's a bike!
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #11 on: Jun 24th, 2012, 8:20pm » |
Quote Modify
|
Ok, next issue I have noticed is that when reconnecting the battery even with the ignition off, keys out etc, and nothing switched on at all it seems like the injectors are energising as I can hear them click open and a short hiss of fuel go through them, I'm sure that cant be correct!
|
|
IP Logged |
My other car's a bike!
|
|
|
Mike H
Senior Member
Renault Clio
Posts: 2594
|
|
Re: Rev counter not working.
« Reply #12 on: Jun 25th, 2012, 11:25am » |
Quote Modify
|
This is starting to sound like a rotten wiring loom problem
|
|
IP Logged |
Mike H
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #13 on: Jun 25th, 2012, 5:25pm » |
Quote Modify
|
Hi all, well I have some further developments in the saga, I replaced the ignition lock relay this morning and this has cured the injectors energising when reconnecting the battery, the cooling fan issue was an intermittent connection at the green relay due to the connector not locking in properly, I now also have fully functioning reversing lights, passenger dipping mirror and the auto dim interior mirror is working properly too, so at least I have resolved a lot of other problems along the way. I still have no rev counter as yet although it did decide to work for a while this morning on the way to the shops so it seems it is just a dodgy connection somewhere, I will check all the contacts at the EDIS module and the ignition switch next. In the meantime if anyone has any other ideas they will be greatly appreciated. Thanks.
|
|
IP Logged |
My other car's a bike!
|
|
|
Simmo
Administrator
I'm an OAP !
Posts: 5508
|
|
Re: Rev counter not working.
« Reply #14 on: Jun 26th, 2012, 6:28am » |
Quote Modify
|
I take it that the relay you refer to is No:21 in the Auxillary fusebox?. Interesting to note the 'connection' to the reversing lights, passenger and interior mirror. Are the reversing lights standard or an aftermarket unit?.
|
|
IP Logged |
Now I'm an OAP
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #15 on: Jun 27th, 2012, 1:15pm » |
Quote Modify
|
Hi again, I have some more developments in the battery discharge saga. Today I connected my multimeter through the battery positive lead as described in the fault finding section, immediately finding a current drain of almost 1.8 amps. So I started pulling fuses one at a time to see when it would stop, removing the 30 amp fuse, no: 44 in the auxiliary fusebox, (cooling fans) stops the current drain. Anyway to play safe I then disconnected the fan relay and also the fans themselves and then replaced the fuse, surprisingly the current drain is still there at almost 1.8 amps, so my question now is what other circuits if any does fuse 44 supply. This was done with the ignition switched off and key out, all doors closed, so no other things draining power.
|
|
IP Logged |
My other car's a bike!
|
|
|
Simmo
Administrator
I'm an OAP !
Posts: 5508
|
|
Re: Rev counter not working.
« Reply #16 on: Jun 27th, 2012, 5:06pm » |
Quote Modify
|
According to This from Snoopy's wiring details it seems to be the main engine control!.
A further look produces This diagram which appears to relate to the cooling fans!. Scroll to page 28.
|
|
IP Logged |
Now I'm an OAP
|
|
|
Bikerdon
Full Member
2.0 Ultima saloon, Norton 500, Suzuki 550.
Posts: 129
|
|
Re: Rev counter not working.
« Reply #17 on: Jun 29th, 2012, 9:12am » |
Quote Modify
|
Hi again, and thanks for the extra info Simmo, well I decided to play safe and rebuild the battery side fusebox, no problems with that as it is all clean and dry. What I did do as I was reconnecting it was to keep my multimeter connected as suggested before to see which of the connectors underneath relates to the current drain, it seems to relate to whatever is connected by connectors C421 (white) and C321 (green), any suggestions folks!
|
|
IP Logged |
My other car's a bike!
|
|
|
Simmo
Administrator
I'm an OAP !
Posts: 5508
|
|
Re: Rev counter not working.
« Reply #18 on: Jun 29th, 2012, 11:07am » |
Quote Modify
|
Can you not relate these connectors to the appropriate fuses/relays?. Ive tried to work it out from the site without success!. 
|
|
IP Logged |
Now I'm an OAP
|
|
|
Mike H
Senior Member
Renault Clio
Posts: 2594
|
|
Re: Rev counter not working.
« Reply #19 on: Jun 29th, 2012, 1:34pm » |
Quote Modify
|
If it's 2.0L 16V then it's this diagram, page 24:
ENGINE CONTROL 2-0L 16V
1.8A suggests a resistance to ground of about 6.5 Ohms.
If you've been messing with the fusebox which fuse F44 is in there could still be something wrong with it causing the short. Perversely, of course, it's not enough to blow the fuse.
E.g. in the fusebox, what is P1, "busbar" ?
Or, a pair of shorted wires could do that as well. E.g. wiring to the fan relay.
|
|
IP Logged |
Mike H
|
|
|
|
Home
Help
Search
Members
Login
Reply
Send Topic
Print